The present invention relates to knee braces, and more particularly, to knee brace assemblies in conjunction with continuous passive motion (hereinafter “CPM”), which incorporate bladders, and which are adapted for use in a thermal or contrast therapy system, or medical thermal therapy system. The bladder element of the present invention enables the user to obtain a tightly controlled and consistent temperature or contrast therapy, along with support, pressure and/or compression therapy. Additionally, the knee brace includes an intelligent joint, capable of being configured to a range of flexion and transmitting the instant angle and the configured range of flexion to the continuous passive motion device.
Knee impairments affect over 13.5 million people in the United States in 2001. Knee impairments account for almost half of the musculoskeletal impairments in the United States. The knee is the largest joint in the body, and its exposed position makes it vulnerable to injury during activities. Knee impairments affect a person's ability to walk, crouch, climb and otherwise move freely. Additionally, knee impairments can be extremely debilitating and painful.
Knee braces are commonly utilized to alleviate pain, provide stability, increased mobility, and reduced healing time after injury, medical procedure or ailment of the knee. Knee braces may be rigid or semi-rigid, providing medial and lateral knee stability to protect the medial and lateral collateral ligaments, meniscus and joint cartilage. Adjustable hinges may be included to provide protection of the ACL and PCL ligaments. Flexion and extension stops may be included to control knee joint range of motion. Additionally, by wrapping tightly around the leg the knee brace may provide compressive therapy. Knee braces alleviate pain and allow damaged tissue to properly heal and rehabilitate.
In addition, it is often important to flex and extend therapy sites in order to provide effective therapy. A prescribed therapeutic regime may include a regimen of flexing and extending the implicated site. In addition to flexure and extension, active physical therapy may include additional holding and stretching with the assistance of a physical therapist or physician. Such additional flexing, stretching and holding at certain points within the critical or working range of motion, as well as flexing and extending through an appropriate therapeutic range of motion, may help increase the rate of rehabilitation.
In addition to active physical therapy, systems and methods of applying passive therapeutic motion have been developed. The therapeutic use of an external force to flex and extend the limb to induce motion is referred to as passive motion. The application of continuous passive motion (CPM) to a joint following a period of immobilization, injury, surgery or the like, has been shown to reduce post-operative pain, decrease the number of adhesions, decrease the amount of atrophy experienced by the surrounding and supporting muscle, promote the speed of recovery, improve the range of motion in a much shorter time, and reduce the risk of deep vein thrombosis. Depending on the nature and severity of the injury or the nature and extent of the surgical procedure performed, therapeutic treatment sessions involving continuous passive motion may be carried out on a daily basis for several days or several weeks.
Conditions commonly requiring a knee brace or CPM include, but are not limited to, postoperative rehabilitation period for total knee arthroplasty, replacement as an adjunct to on-going physical therapy, anterior cruciate ligament repair, surgical release of arthrofibrosis/adhesive capsulitis, intra-articular cartilage fractures, Chondroplasties of focal cartilage defects, osteochondritis dissecans, abrasion arthroplasty or microfracture procedure, intra-articular fracture of the knee (e.g., tibial plateau fracture repair), autologous chondrocyte transplantation, reflex sympathetic dystrophy, dupuytren's contracture and extensive tendon fibrosis. Of all the applications of CPM, the scientific evidence is perhaps strongest for its use in promoting cartilage growth. In addition, clinical studies suggest that CPM can enhance cartilage healing during the non weight bearing period following surgery for intra-articular cartilage fractures, chondroplasties of focal cartilage defects and surgical treatment of osteochondritis dissecans.
In most patients after extensive joint surgery, attempts at joint motion cause pain and as a result, the patient fails to move the joint. This allows the tissue around the joint to become stiff and for scar tissue to form resulting in a joint which has limited range of motion and often may take months of physical therapy to recovery that motion.
The concept of using CPM in conjunction with therapy is not new. A number of known devices that are designed to impose CPM on the limb and joint of a patient for such a purpose are in use in therapeutic settings. While the incorporation of CPM into therapeutic treatment is well known, the ability to effectively apply thermal therapy while the therapy site is in active or passive motion has heretofore been unknown. The use of thermal therapy may increase the effectiveness of a therapeutic regimen of motion. For instance, implicated therapy sites are often sore upon entrance into therapy. The use of heat or cold therapy may help to reduce pain and, therefore, increase the amount of time a patient may endure CPM therapy. Heat therapy may help increase blood flow to the implicated site. Heat therapy may also be used to relax joint tissue, such as ligaments and tendons, to increase range of motion in a CPM setting.
Cold therapy, on the other hand may help to reduce swelling, decrease pain, and promote healing of injured tissue. Both heat and cold therapy may help increase the effectiveness of rehabilitation. Given that there is often pain associated with CPM during the application of CPM therapy, it is important to find effective ways of reducing pain during the therapy. Key benefits of having thermal therapy during CPM are to help increase mobility with heating and to help reduce pain with cooling. Additionally, the instant contrast therapy exchange layer provides constant compression at the therapy site in flexure. Compression aids in reducing swelling and may help to stabilize the therapy site in flexure. As such, the use of contrast therapy in conjunction with CPM may provide the most effective therapy.
Traditionally, the knee brace is worn separately from the CPM device, and is removed prior CPM therapy. Removal of the knee brace prior to CPM therapy may be physically difficult, painful and time consuming. The effectiveness of a therapy is dependent on the ease in which the therapy may be applied. If it is difficult for a therapy recipient to self apply a therapy, the opportunity to receive therapy may be diminished. Furthermore, if therapies are complicated and/or uncomfortable, a therapy recipient is less likely to undergo the therapy, although it may be beneficial.
It is therefore apparent that an urgent need exists for an improved knee brace that integrates the added benefits of contrast therapy and simultaneous use with a continuous passive motion device. This assembly would be able to provide a high level of knee joint support, readily compatible with CPM therapy, and with the addition of a thermal therapy that may be very well regulated.